Apparatus and method for straightening extruded bar stock



APPARATUS AND METHOD FOR STRAIGHTENING EXTRUDE D B A R S T O CKINVENTORS. fl/exw Mach/W64 i j iayJ 27 6747/? P 1966 A. N. SOKOLOFF ETAL3,271,985

APPARATUS AND METHOD FOR STRAIGHTENING EXTRUDED BAR STOCK Filed Jan. 14,1964 5 Sheets-Sheet 2 m 04%; aa

R STOCK p 13, 1966 A. N. SOKOLOFF ETAL APPARATUS AND METHOD FORSTRAIGHTENING EXTRUDED BA m m Q MN R Q m? Em N a r .W F W344 a w 0 ZUnited States Patent M APPARATUS AND METHOD FOR STRAIGHT- ENING EXTRUDEDBAR STOCK Alexis N. Sokoloif and Floyd E. Clark, Port Huron,

Mich., assignors to Mueller Brass C0,, Port Huron, Mich., a corporationof Michigan Filed Jan. 14, 1964, Ser. No. 337,637

11 Claims. (Cl. 72256) This invention relates to extruded metal barstock, and more particularly to means for straightening certain types ofbar stock, such as alloy stock, which are hot extruded with crosssections of rectangular outline and which cannot be straightened aftercooling because of brittleness in the cold form.

It is an object of the invention to provide a novel and improved methodand apparatus for straightening bar stock while hot which greatlyreduces the time required between the extruding of the bar and theactual straightening thereof, thus resulting in a more uniform stocktemperature when the initial straightening force is applied.

It is another object to provide an improved bar stock straighteningmethod and apparatus of this character which increases the accuracy withwhich the stock can be straightened, thus permitting relatively longlengths of stock to be held to close straightness tolerances.

It is a further object to provide an improved straight ening method andapparatus of this nature which is much faster than previously knownstraightening systems for extruded stock, even for long stock lengths.

It is another object to provide an improved apparatus and method of thischaracter which is flexible in nature, can be used to straighten bars ofdifferent lengths, and can be varied to permit different cooling periodswhile compression is maintained on the stock so that the cooled stockwill retain its straightness after removal from the apparatus.

It is also an object to provide an improved method and apparatus of thisnature which can simultaneously handle a number of bars delivered from asingle extruding station in a minimum of space, thus permittingincreased productivity of the extruding station.

Other objects, features and advantages of the present invention willbecome apparent from the subsequent description, taken in conjunctionwith the accompanying drawings.

In the drawings:

FIGURE 1 is a diagrammatic view of a straightening installation usingthe principles of this invention;

FIGURE 2 is a perspective view of the first and fourth stations of theinstallation showing the cross or lateral conveyors;

FIGURE 3 is an end elevational view of the first station showing thevertical straightening members and the carriage construction;

FIGURE 4 is a side elevational view of one of the cross conveyors;

FIGURE 5 is a side elevational view of one of the power-drivenlongitudinal conveyors; and

FIGURE 6 is a top plan view of the conveyor of FIG- URE 5.

Briefly, the illustrated embodiment of the invention comprises achannel-shaped carriage adapted to receive hot extruded bar stock fromthe extruding table, the carriage initially resting at a first stationaligned with the extruder. Vertically movable clamps or straighteningmembers of elongated shape are pressed down by fluid motors onto thestock within the carriage to straighten 3,271,985 Patented Sept. 13,1966 it in a vertical direction by engaging the entire length of stockand pressing it against the flat floor of the carriage. Elongatedscrew-operated horizontally movable straightening members mounted withinthe carriage are then actuated to straighten the stock in a horizontaldirection, likewise engaging it along its entire length and pressing itagainst the opposite flat side wall of the carriage. The

7 vertical clamps are then lifted, and the carriage is transportedlongitudinally by power-driven rollers at the first station to a secondstation aligned with the first station and having idling rollers.

Tiltable laterally extending roller conveyors then lift the carriagefrom the second station and transport it to a third station which alsohas power-driven rollers for transporting the carriage longitudinallyback toward a fourth station located opposite the first station andhaving idling rollers. A second set of laterally extending tiltableconveyors then transport the carriage back to the first station. Duringtransport to the second, third, fourth and first stations, thehorizontal clamps will maintain compression on the stock. Afterreturning to the first station, the horizontal clamps will be releasedand the cooled and straightened stock removed from the carriage,permitting it to be reloaded from the extruding table. When continuouslyoperating, three carriages may be simultaneously used, the carriagesbeing distributed among the four stations. Intermediate stations may beadded as required, thus increasing the number of carriages which may besimultaneously used.

Referring more particularly to the drawings, and first to FIGURE 1, 11represents schematically an extrusion station which may be used to hotextrude certain bar stock alloys which cannot be straightened aftercooling because of the brittle properties of the cooled stock. Thestock, which may have any of various cross sections of rectangularoutline, leaves station 11 in a rightward direction and is delivered toan extruder deli-very table 12.

The apparatus of this invention is generally indicated at 13 andincludes a first conveyor generally indicated at 14 and a secondconveyor generally indicated at 15, conveyors 14 and 15 being alignedwith extruder table 12, a third conveyor generally indicated at 16alongside and laterally spaced from conveyor 15, and a fourth conveyorgenerally indicated at 17 aligned with conveyor 16 and laterally spacedfrom conveyor 14.

The construction of conveyor 14 is perhaps best seen in FIGURES 2, 3, 5and 6. The conveyor comprises a plurality of spaced base members 18,seen in FIGURE 5, upon which rest a pair of parallel longitudinallyextending lower beams 19 with a pair of roller-supporting upper beams 21resting on beams 19 but not attached thereto. A plurality oflongitudinally spaced pedestals 22 are provided, as seen in FIGURE 5,and carriage supporting cross beams 23 rest on pedestals 22, beams 23being slightly shorter than the distance between beams 21. The height ofthe flat upper surfaces of beams 23 is such that they will be slightlyabove the level of the rollers carried by beams 21 when the latter reston beams 19.

Beams 21 are secured together by cross members 24 and rotatably supporta plurality of longitudinally spaced rollers 25, the tops of rollers 25being slightly above the level of the upper surfaces of beams 21. Amotor 26 is mounted at one end of beams 21, and drives rollers 25through a plurality of chains and sprockets 27 which connect the rollershafts in succession on the outside of one beam 21, as seen in FIGURE 6.

Means are provided for selectively lifting beams 21 and their rollersfrom their lower FIGURE 5 position to an upper position (indicatedpartially by the dot-dash line in FIGURE 5) in which the level of thetops of rollers will be above the level of the tops of beams 23, therebypermitting a carriage (described below) to be longitudinally driven bythe rollers. This means includes a fluid-operated reciprocating motor 28which is secured at one end to a base member 18 and at the other end toa longitudinally extending bar 29 between beams 19, as seen in FIGURE 5.A plurality of longitudinally spaced bell cranks 31 are pivoted at 32 tobeams 19 and have one arm connected to bar 29. The other arms of thesebell cranks have rollers 33 engageable with the flat undersides of crossmembers 24. The arrangement is such that rightward movement of bar 29from its FIGURE 5 position will cause counterclockwise movement of bellcranks 31, thus lifting beams 21 and their rollers. Guide members 34 maybe secured to the upper portions of beams 19 for preventing unwantedlateral shifting of beams 21 during this movement.

A pair of vertically movable clamping or straightening members 35 and 36are also mounted at station 14, as seen in FIGURE 2. These memberscomprise rigid bars of rectangular cross-sectional shape with fiatundersides, the bars being in aligned relation and secured to the lowerends of piston rods 37 of a plurality of fluid-actuated reciprocatingmotors 38, as seen in FIGURE 3, the connection being a pivotal one asindicated in this figure to permit adjusting movement of members 35during the straightening process. The other ends of fluid motors 38 aresecured to the undersides of longitudinally extending beams 39 which aredisposed above the conveyor shown in FIGURES 5 and 6. Beams 39 aresuspended from a pair of cross tracks 41 and 42 supported above theopposite ends of conveyor 14 by uprights 43, as seen in FIGURE 2, wheels44 being rotatably carried by the opposite ends of beams 39 and restingon both sides of tracks 41 and 42. This will permit simultaneous lateraladjustment of clamping members 35 and 36 by means of a pair offluid-actuated reciprocating motors 45 connected between a beam 39 anduprights 43, as seen in FIGURE 3.

The provision of two separate aligned vertically movable straighteningmembers 35 and 36 will permit the clamping of relatively short lengthsof stock, using only one of the two members. For this purpose, fourmotors 38 are used to support and actuate member 35 and four additionalmotors are used for member 36, as seen in FIGURE 2.

A carriage 46 of generally channel-shaped construction is provided, thecarriage having a floor or web portion 47, a first side wall 48 and asecond side wall 49. The underside of carriage 46 is adapted to ridelongitudinally on rollers 25, and is also adapted to ride laterally ontransverse conveyor rollers which are described below. A pair ofhorizontal straightening members 51 and 52 is disposed in carriage 46,these members comprising rigid bars of rectangular cross-sectional shapehaving flat surfaces facing wall 48. A plurality of screw actuators 53are provided for sliding members 51 and 52 either to the left or to theright, as seen in FIGURE 3. Four such actuators are shown forstraightening member 51 and four for straightening member 52, as seen inFIGURE 2. Straightening members 51 and 52 are coextensive withstraightening members 35 and 36 respectively, so that shorter lengths ofstock may be straightened by using only one pair of straighteningmembers.

The means for rotating the screw actuators 53 for each member 51 or 52comprises a rod 54 which is mounted on carriage 46 outside wall 49, andis rotatable by a hand wheel 55, as seen in FIGURE 3, the two handWheels being at opposite ends of carriage 46. Rods 54 are connected toworm and worm gear mechanisms (not shown) within housings 56 which aresecured to the outside wall 49 and surround actuating screws 53. Thearrangement is such that rotation of either hand wheel 55 I in onedirection will result in rightward movement of straightener 51 or 52,while rotation in the other direction will result in leftward orretracting movement of the corresponding straightener, the straightenersremaining parallel with side wall 48. The mechanical advantage of theactuating mechanism is such that manual rotation of either hand wheel 55by an operator will create sufficient force to straighten a hot extrudedbar 57 which is held down by vertical straightener 35 or 36 by pressingthe bar against side wall 48, as seen in FIGURE 3. The length ofactuators 53 will of course be sufficient to afford the desired travelof straighteners 51 and 52. Guard bars 58 are secured outwardly of andin spaced relation with actuators 53, as seen in FIGURE 3, to protectthe screw actuators from impact during handling, these guard bars 58being secured to carriage 46 by members 59. Sleeves 61 may also beprovided for protecting the outside portions of the actuator screws.

Conveyors 15 and 17 are alike, and conveyor 17 is shown in detail inFIGURE 2. The conveyor comprises a plurality of longitudinally spaceduprights 62 which extend laterally, and on which are mounted a pair ofspaced parallel frame members 63 and 64. Longitudinally spaced rollers65 are rotatably mounted between frame members 63 and 64. These rollersare not powerdriven but are idling rollers so that when carriage 46 isdischarged from conveyor 14, it will roll to a stop on conveyor 15, andwhen discharged from conveyor 16, it will roll to a stop on conveyor 17.

Conveyor 16 is constructed in a manner similar to conveyor 14 and inparticular has power-driven rollers. However, the vertical straighteningmembers are absent from the vicinity of conveyor 16, as are the supports23 in their bases 22 which serve to counteract the force exerted bymembers 35 and 36 when the carriage is at conveyor 14. The means forraising and lowering the rollers (motor 28 and its associated mechanism)is also absent from conveyor 16.

Means are provided for transferring carriages laterally from conveyor 15to conveyor 16 and from conveyor 17 to conveyor 14. These means comprisea plurality of tiltable roller conveyors generally indicated at 66extending between conveyors 15 and 16, and tiltable roller conveyorsgenerally indicated at 67 between conveyors 17 and 14. Downwardlyextending clearance recesses 68 indicated in FIGURES 4 and 5 areprovided in the inwardly facing frame members of conveyors 14 through17, and these recesses accommodate lateral conveyors 66 and 67. Theconstruction of the lateral conveyors is perhaps best seen in FIGURES 2and 4. Each lateral conveyor has a pair of spaced parallel frame members69 and 71 between which extend a plurality of spaced rollers 72, thetops of these rollers being above the level of the frame members. Oneend of the frame members is secured by a horizontally extending pivot 73to frame members 19 of conveyors 16 (in the case of lateral conveyors66) or to frame members 19 of conveyor 14 (in the case of lateralconveyors 67). In each case, pivot 73 is located adjacent the outer edgeof the conveyor, and slightly below the tops of the rollers, as seen inFIGURE 4. The other end of each lateral conveyor 66 or 67 is adapted tobe raised or low ered by a fluid-operated reciprocating motor 74, thecylinder of this motor being pivotally secured at 75 to a base 76, whilethe upwardly extending piston 77 is pivotally connected at 78 to a crossmember 79 extending between the frame members 69 and 71. In the lowerposition of a motor 74, its conveyor 66 or 67 is inclined slightlydownwardly toward the motor, as seen in FIGURE 4, and the rollers 72 atboth ends of the conveyor are lower than the rollers on the adjacentlongitudinal conveyors. When motor 74 is extended, however, conveyor 66or 67 will be swung upwardly, (counterclockwise in FIGURE 4) and willlift up a carriage 46 resting on a longitudinal conveyor 15 or 17. Forthis purpose, the length of lateral conveyors 66 and 67 is such thatthey extend almost to the outer edges of conveyors and 17 respectively.All lateral conveyors 66m 67 will be simultaneously actuated so that theentire carriage 46 will be lifted, and since it then rests solely on thelateral conveyors, it will roll laterally downhill toward conveyor 16 or14. Appropriate stop means (not shown) may be provided for stopping thecarriage when it reaches conveyor 16 or 14, or the tilting of thelateral conveyors 66 and 67 may be controlled so that the carriage slowsdown and stops when in its proper position.

In operation, an empty carriage 46 will be placed on conveyor 14,vertical straightening members 35 and 36 being retracted upwardly, andwith rollers and frame members 21 in their lowered positions, as shownin solid lines in FIGURE 5, so that carriage 46 rests on cross beams 23.It should be observed that the size of recesses 68 should be sufiicientto permit raising and lowering of rollers 25 without interference bylateral conveyors 66 and 67. One or more lengths of stock from extrudertable 12 will be placed in carriage 46, and vertical straighteningmembers and 36 will be lowered by motors 38, pressing down on stock 57and straightening it in a vertical direction by forcing it onto floor47. It should be noted that either one or both of straightening members35 and 36 may be used, depending upon the number and length of the stockbars. In any case, the straightening members will simultaneously engagethe stock along its entire length, and due to their rigidity willstraighten the stock in an even manner. While the stock is so held,horizontal straightening members 51 and 52 will be moved to the right inFIGURE 3 by rotation of hand wheels 55 which in turn will rotate screwactuating members 53. This will cause stock 57 to be straightened in ahorizontal direction by pressing it against side wall 48 of carriage 46.It should be noted that in the cases of both vertical and horizontalclamping members, pressure'will be evenly exerted along the entirelength of the stock.

While the horizontal straightening members 51 and 52 maintaincompression on the stock, vertical straightening members 3 5 and 36 willbe lifted by motors 3 8. Motor 28 will then be operated to lift framemembers 21 and rollers 25, along with carriage 46, off cross beams 26.The carriage may then be moved endwise in a straight line by operationof motor 26 which will rotate rollers 25. This will cause carriage 46-to arrive on conveyor 15. After a time delay of predetermined length,the carriage will be transported from conveyor 15 to conveyor 16 byupward tilting of lateral conveyors 66, as seen in FIG- URE 4. Uponarrival at conveyor 16, carriage 46 will remain for a predetermined timeinterval and will then be transported to conveyor 17 by operation of thepowerdriven rollers 2-5 of conveyors 16. Upon arrival at conveyor 17,the carriage will again rest for a predetermined time and will then betransported back to conveyor 14 by tilting of lateral conveyors 6-7. Allduring this time, horizontal straightening me lbers 51 and 52 will beexerting horizontal straightening pressure on stock 57, and will alsohold the stock in its vertically straightened position because of thefact that the stock is frictio-nally gripped between members 51 and 5 2and wall 48. Upon return to conveyor 14, the horizontal clamping memberswill be released by hand wheels 55, and the stock will be removed,completing the cycle. By the time the stock is removed, it will havecooled sufficiently to retain its straightness.

It will be observed that three carriages 46 could be simultaneously usedin the system shown in FIGURE 1, there being at all times a carriage atthree of the four conveyors 14 through 17. The carriages would then betransported in succession around the circuit of the four conveyors. Thetiming of the successive transports and delays could of course be sochosen as to achieve the desired cool-ing of the stock, and to permitunloading and reloading of each carriage 46 as it reaches conveyor 14.Moreover, by placing two intermediate longitudinal con- 5. veyors in thesystem, one between conveyors 1 4 and 15 and one between conveyors 16and 1 7, five carriages could be simultaneously used. In like manner,additional intermediate conveyors could increase the number ofsimultaneously usable carriages.

It will thus \be observed that a novel and improved straighteningapparatus and method have been provided which enable hot extruded barstock to be straightened to close tolerances while still hot, in asimple and efficient manner requiring a minimum of time and space, whilefacilitating maximum productivity of the extruder.

While it will be apparent that the preferred embodi ment of theinvention disclosed is well calculated to fulfill the objects abovestated, it will be appreciated that the invention is susceptible to'modification, variation and change without departing from the properscope or fair meaning of the subjoined claims.

What is claimed is:

1. In a method for straightening bar stock, the steps of supporting thebar stock along its entire length against pressure directed in twoperpendicular direction-s, exerting pressure simultaneously along theentire length of said stock in one of said directions, exerting pressurealong the entire length of said stock in the other direction while thefirst-mentioned pressure is still being applied, removing thefirst-mentioned pressure while still applying the second-mentionedpressure, transporting said stock while still maintaining saidsecond-mentioned pressure to a series of stations and then back to saidfirst station, and removing said second-mentioned pressure when saidstock reaches said first station.

2. In a method for straightening extruded bar stock having a crosssection of rectangular outline, the steps of supporting twoperpendicular surface of said bar stock continuously along their entirelength, pressing a third surface of said bar stock at a first stationcontinuously along its entire length toward one of said first twosurfaces, pressing a fourth surface of said bar stock at said firststation continuously along its entire length toward the other .of saidfirst two surfaces while maintaining said first-mentioned pressure,releasing sa'id first-mentioned pressure, transporting said bar stockfrom said first station while maintaining said second-mentionedpressure, permitting said bar stock to cool, while maintaining saidsecond-mentioned pressure, sufiiciently to retain its straightened shapeafter pressure release, and releasing said second-mentioned pressure.

3. In a method for straightening extruded bar stock having a crosssection of rectangular outline, the steps of supporting twoperpendicular surfaces of said bar stock continuously along their entirelength, pressing a third surface of said bar stock at a first stationcontinuously along its entire length toward one of said first twosurfaces, pressing a fourth surface of said bar stock at said firststation continuously along its entire length toward the other of saidfirst two surfaces while maintaining said-first mentioned pressure,releasing said first-mentioned pressure, permitting said bar stock tocool, while maintaining said second-mentioned pressure, sufiiciently toretain its straightened shape after pressure release, and releasing saidsecond-mentioned pressure.

4. In a straightening apparatus for extruded bar stock of predeterminedlength, an elongated carriage having a floor and a side wall and adaptedto support a hot extruded bar of stock, a vertical straightening membermounted above said carriage and having a flat surface facing saidcarriage and extending the entire length of said bar stock, means foractuating said straightening member between an upper retracted positionaway from said stock in a lower straightening position forcing saidstock against said carriage floor, a horizontal straightening memberslidably disposed above said carriage floor and at least as long as saidpredetermined bar stock length, and means for actuating said horizontalstraightening member between a retracted position away from 7 said barstock and a straightening position engaging said bar stock along itsentire length and forcing it against said carriage side wall.

5. The combination according to claim 4, said vertical and horizontalstraightening members each comprising a rigid bar of rectangularcross-sectional shape, said means for actuating said verticalstraightening member comprising a plurality of reciprocablefluidactuated motors suspended above said carriage, said means foractuating said horizontal straightening member comprising a plurality ofscrew actuators mounted on the side of said carriage opposite said sideWall, and means for simultaneously operating said screw actuators.

6. In a straightener for hot extruded bar stock of rectangularcross-sectional outline and predetermined length, an elongated carriagehaving a channel-shaped cross-section with a fiat floor and a flat sidewall on one side thereof, a framework suspended above said carriage, ahorizontally extending vertical straightening member having a fiatsurface facing the floor of said carriage, mot-or means for moving saidstraightening member between upper retracted and lower straighteningpositions, a horizontally extending horizontal straightening memberhaving a flat surface facing the side wall of said carriage and disposedabove the floor thereof, and means on said carriage for moving saidhorizontal straightening member between a retracted position withdrawnfrom said side wall and a straightening position forcing a bar of stockagainst said side well, said last-mentioned means maintaining saidhorizontal straightening member parallel to said side wall during saidmovement.

7. In a straightener for hot extruded bar stock of rectangularcross-sectional outline and predetermined length, an elongated carriagehaving a channel-shaped cross section with a flat floor and a fiat sidewall on one side thereof, a framework suspended above said carriage, ahorizontally extending vertical straightening member having a flatsurface facing the floor of said carriage, motor means for moving saidstraightening member between upper retracted and lower straighteningpositions, a horizontally extending horizontal straightening memberhaving a Hat surface facing the side wall of said carriage and disposedabove the floor thereof, means on said carriage for moving saidhorizontal straightening member between a retracted position withdrawnfrom said side wall and a straightening position forcing a bar of stockagainst said side wall, said last-mentioned means maintaining saidhorizontal straightening member parallel to said side wall during saidmovement, a roller conveyor supporting said carriage, means forrotatably driving at least some of the rollers on said conveyor andthereby moving the carriage horizontally, and a second roller conveyorfor receiving the carriage after being moved from said first rollerconveyor.

8. In a straightening apparatus for extruded bar stock of predeterminedlength having a cross-sectional shape of rectangular outline, parallelfirst, second, third and fourth roller conveyors arranged in arectangular pattern, an elongated carriage having a flat floor and aflat side surface for supporting perpendicular surfaces of said barstock, a flat elongated vertically movable straightening membersuspended above said first conveyor and movable between a retractedupper position and a lower position forcing said bar stock against saidcarriage floor, a second flat elongated straightening member mounted onsaid carriage and movable between a retracted position and astraightening position forcing said bar stock against said carriage sidewall, both of said straightening members being simultaneously engageablewith said bar stock along its entire length, and means for transportingsaid carriage successively from said first to said second conveyor, fromsaid second to said third conveyor, from said third to said fourthconveyor, and from said fourth to said first conveyor.

In a straightening apparatus for extruded bar stock of predeterminedlength having a cross-sectional shape of rectangular outline, parallelfirst, second, third and fourth roller conveyors arranged in arectangular pattern, an elongated carriage having a flat floor and aflat side surface for supporting perpendicular surfaces of said barstock, a fiat elongated vertically movable straightening membersuspended above said first conveyor and movable between a retractedupper position and a lower position forcing said bar stock against saidcarriage floor, a second flat elongated straightening member mounted onsaid carriage and movable between a retracted position and astraightening position forcing said bar stock against said carriage sidewall, both of said straightening members being simultaneously engageablewith said bar stock along its entire length, and means for transportingsaid carriage successively from said first to said second conveyor, fromsaid second to said third conveyor, from said third to said fourthconveyor, and from said fourth to said first conveyor, said first andsecond conveyors and said third and fourth conveyors beinglongitudinally aligned, said means for transporting the carriage fromsaid first to said second and from said third to said fourth conveyorscomprising power means for rotating the rollers of said first and thirdconveyors.

10. In a straightening apparatus for extruded bar stock of predeterminedlength having a cross-sectional shape of rectangular outline, parallelfirst, second, third and fourth roller conveyors arranged in arectangular pattern, an elongated carriage having a flat floor and aflat side surface for supporting perpendicular surfaces of said barstock, a flat elongated vertically movable straightening membersuspended above said first conveyor and movable between a retractedupper position and a lower position forcing said bar stock against saidcarriage floor, a second flat elongated straightening member mounted onsaid carriage and movable between a retracted position and astraightening position forcing said bar stock against said carriage sidewall, both of said straightening members being simultaneously engageablewith said bar stock along its entire length, and means for transportingsaid carriage successively from said first to said second conveyor, fromsaid second to said third conveyor, from said third to saidfourthconveyor, and from said fourth to said first conveyor, said second andthird and said fourth and first conveyors being in spaced parallelrelation alongside each other, the means for transporting said carriagefrom said second to said third and from said fourth to said firstconveyors comprising laterally extending roller conveyors tiltable onaxes parallel to said first-mentioned conveyors and having a lowerposition beneath the level of said first-mentioned conveyor and a raisedposition lifting said carriage from said second or fourth conveyor sothat it will roll down to said third or first conveyor.

11. In a straightening apparatus for extruded bar stock of predeterminedlength having a cross-sectional shape of rectangular outline, parallelfirst, second, third and fourth roller conveyors arranged in arectangular pattern, an elongated carriage having a flat floor and aflat side surface for supporting perpendicular surfaces of said barstock, a flat elongated vertically movable straightening membersuspended above said first conveyor and movable between a retractedupper position and a lower position forcing said bar stock against saidcarriage floor, means for moving said vertical-1y movable straighteningmember comprising a plurality of fluid-actuated reciprocating motorsextending downwardly from a framework above said first conveyor, asecond fiat elongated straightening member mounted on said carriage andmovable between a retracted position and a straightening positionforcing said bar stock against said carriage side wall, means for 9 10moving said second straightening member comprising a References Cited bythe Examiner plurality of screw actuators on said carriage and meansUNITED STATES PATENTS for simultaneously operatmg them, both of saidstralghtening members being simultaneously engageable with said $708,5115/1955 Wllson et 72 257 bar stock along its entire length, and means fortrans- 5 3,051,216 8/1962 Tomka et 72 374 porting said carriagesuccessively from said first to said 3,157,268 11/1964 Anderson 72 257second conveyor, from said second to said third conveyor, from saidthird to said fourth conveyor, and from said CHARLES LANHAM PnmaryEmmmer' fourth to said first conveyor. R. D. GREFE, Assistant Examiner.

1. IN A METHOD FOR STRAIGHTENING BAR STOCK, THE STEPS OF SUPPORTING THEBAR STOCK ALONG ITS ENTIRE LENGTH AGAINST PRESSURE DIRECTED IN TWOPREPENDICULAR DIRECTIONS, EXERTING PRESSURE SIMULTANEOUSLY ALONG THEENTIRE LENGTH OF SAID STOCK IN ONE OF SAID DIRECTIONS, EXERTING PRESSUREALONG THE ENTIRE LENGTH OF SAID STOCK IN THE OTHER DIRECTION WHILE THEFIRST-MENTIONED PRESSURE IS STILL BEING APPLIED, REMOVING THEFIRST-MENTIONED PRESSURE WHILE STILL APPLYING THE SECOND-MENTIONEDPRESSURE, TRANSPORTING SAID STOCK WHILE STILL MAINTAINING SAIDSECOND-MENTIONED PRESSURE TO A SERIES OF STATIONS AND THEN BACK TO SAIDFIRST STATION, AND REMOVING SAID SECOND-MENTIONED PRESSURE WHEN SAIDSTOCK REACHES SAID FIRST STATION.